en Related Fields Related Fields مقاله کامل Full Length/Original Article <p><strong>Background:</strong> Intravenous drug delivery is an advantageous choice for rapid administration, immediate drug effect, and avoidance of first-pass metabolism in oral drug delivery. In this study, the synthesis, formulation, and characterization of atorvastatin-loaded polyurethane (PU) nanoparticles were investigated for intravenous route of administration. <strong>Method:</strong> First, PU was synthesized and characterized. Second, nanoparticles were prepared in four different ratios of drug to polymer through two different techniques, including emulsion-diffusion and single-emulsion. Finally, particle size and polydispersity index, shape and surface morphology, drug entrapment efficiency (EE), drug loading, and<em> in vitro</em> release were evaluated by dynamics light scattering, scanning electron microscopy, and UV visible spectroscopy, respectively. <strong>Results:</strong> Within two methods, the prepared nanoparticles had a spherical shape and a smooth surface with a diversity of size ranged from 174.04 nm to 277.24 nm in emulsion-diffusion and from 306.5 nm to 393.12 in the single-emulsion method. The highest EE was 84.76%, for (1:4) sample in the emulsion-diffusion method. It has also been shown that <em>in vitro</em> release of nanoparticles, using the emulsion-diffusion method, was sustained up to eight days by two mechanisms: drug diffusion and polymer relaxation. <strong>Conclusion:</strong> PU nanoparticles, that were prepared by the emulsion-diffusion method, could be used as effective carriers for the controlled drug delivery of poorly water soluble drugs such as atorvastatin calcium.</p> Drug delivery systems, Nanoparticles, Polyurethanes, Cardiovascular diseases 369 379 http://ibj.pasteur.ac.ir/browse.php?a_code=A-10-1-662&slc_lang=en&sid=1 Behnaz Sadat Eftekhari Yes Biomedical Engineering Department, Amirkabir University of Technology, Tehran, Iran Akbar Karkhaneh No Biomedical Engineering Department, Amirkabir University of Technology, Tehran, Iran Ali Alizadeh No Nanotechnology Research Center, Sharif University of Technology, Tehran, Iran